"If three or more objects move around each other, history cannot be reversed.
That is the conclusion of an international team of researchers based on computer simulations of three black holes orbiting each other. The researchers, led by the Dutch astronomer Tjarda Boekholt, publish their findings in the April issue of the journal Monthly Notices of the Royal Astronomical Society.
Most basic laws in physics have no problem with the direction in which they run. They are, as scientists call it, symmetric with respect to time, or time symmetric. In practice, however, everyone knows that time cannot simply be turned back. For example, a cup that falls into hundred pieces really does not fly back into your hand spontaneously and undamaged. Until now, scientists explained the lack of time symmetry by the statistical interaction between large numbers of particles. Three astronomers now show that only three particles are enough to break the time symmetry.
Tjarda Boekholt (University of Coimbra, Portugal), Simon Portegies Zwart (Leiden University) and Mauri Valtonen (University of Turku, Finland) calculated the orbits of three black holes that influence each other. This is done in two simulations. In the first simulation, the black holes start from rest. Then they move towards each other and past each other in complicated orbits. Finally one black hole leaves the company of the two others. The second simulation starts with the end situation of two black holes and the escaped third black hole and tries to turn back the time to the initial situation."
https://www.infowars.com/time-symmetry-and-the-laws-of-physics/